3 thoughts on “Amigos Podcast Episode 112 – Sly Spy: Secret Agent”

Nice podcast episode as usual, thanks guys!
I listened to that one two weeks ago while driving from Montreal to Vermont to participate in an estate sale where a lady was selling a (huge) number of retro computing stuff so that was a particularly appropriate listen!

I am way less tolerant to the Sly Spy Amiga version than you guys seem to be. Although the game is graphically nice I share Aaron’s opinion that this monster HUD is both unnecessary and ungraceful and for a very specific reason: it is a vestigial artifact of the game’s origins on the ST.
Sly Spy unfortunately belongs to the infamous “ST port” category: games which were very quickly ported from the ST to the Amiga without taking into account any of the (enormous) advantages of the Amiga custom chipset.
The reason for the big HUD (in this game and many others) is simple: speed. Since the ST does not benefit from any hardware scrolling assistance, the graphics must be copied manually by the CPU when scrolling. This implies that the bigger the surface area to scroll, the slower the game will be, which is why for many scrolling ST games the scrolling area is usually made as small as possible thus encouraging the presence of very large HUDs.
The Amiga does not suffer at all from this issue: scrolling a screen requires changing at most a few dozen bytes in memory and the custom chips will do the rest so there is no justification for any kind of HUD. Do Battle Squadron or SWIV have a hud? nope, they gracefully overlay any HUD information on top of the scrolling display as did the Sly Spy Arcade version, and as the Amiga port should have. 🙁

Another tidbit which betrays the ST origins or the port: the ST version benefits from parallax scrolling in the bike section, which the Amiga does not have. Why? Because the ST CPU is clocked slightly higher than the Amiga’s one (about 10%), which gives it the oomph needed to draw that small parallax layer. Since they ported the code without bothering to use the Amiga hardware, they had to do with the slightly slower CPU speed and had to remove the parallax.
The fact that they did not even consider spending one additional day, converting the screen copy routines to at least use the Amiga Blitter for that task (instead of the CPU) says a lot about the love they had for the machine. 🙁

It goes without saying that Sly Spy is also on my list of “to re-port” games. 😉